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From: Vasanthakumar Thiagarajan <vasanth@atheros.com>
To: ath9k-devel@lists.ath9k.org
Subject: [ath9k-devel] Pending ath9k bugs
Date: Tue, 2 Jun 2009 10:39:04 +0530	[thread overview]
Message-ID: <20090602050904.GC17632@vasanth-laptop> (raw)
In-Reply-To: <43e72e890906011252s43d2c596m6ec79569f5074837@mail.gmail.com>

 
> BUG_ON in rc.c when using 11n. This could be caused by an incorrect
> assumption in ath9k that the rc priv is correctly for the target rate.
> The issue may be seen when trying to associate and changing between
> legacy and HT rates on SMP systems when mac80211 passes frames on
> different queues due to multiqueue support. If that is indeed the
> reason for the issue we will probably need locking on the rc priv or
> simply to revamp it. I'll send a patch for now to downgrade the BUG_ON
> but we do need a proper fix for this, it just needs more careful
> review.

I agree that rc priv needs proper locking, but I dont think this
particular issue is related to some race in rc priv. As I already
mentioned in one of the mails related to this problem, the root
cause can be a failure in channel set, have we confirmed that?.
I tried to reproduce this on my setup but no luck.

> 
> While on the topic I should mention a welcomed change would be to
> actually revamp ath9k RC to fix it to correctly report MCS rates to
> mac80211. 

This needs complete rewrite of ath9k rate control alg.


Vasanth

WARNING: multiple messages have this Message-ID (diff)
From: Vasanthakumar Thiagarajan <vasanth@atheros.com>
To: Luis Rodriguez <lrodriguez@atheros.com>
Cc: "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	"parag.warudkar@gmail.com" <parag.warudkar@gmail.com>,
	Gaurav Jauhar <Gaurav.Jauhar@Atheros.com>,
	"fabian.deutsch@gmx.de" <fabian.deutsch@gmx.de>,
	"arxs@fedoraproject.org" <arxs@fedoraproject.org>,
	"linville@tuxdriver.com" <linville@tuxdriver.com>,
	"debaditya@gmail.com" <debaditya@gmail.com>,
	Senthilkumar Balasubramanian
	<Senthilkumar.Balasubramanian@Atheros.com>,
	"drago01@gmail.com" <drago01@gmail.com>,
	"ath9k-devel@lists.ath9k.org" <ath9k-devel@lists.ath9k.org>,
	"michal@harddata.com" <michal@harddata.com>,
	"leann.ogasawara@canonical.com" <leann.ogasawara@canonical.com>,
	"tim.gardner@canonical.com" <tim.gardner@canonical.com>,
	"jirislaby@gmail.com" <jirislaby@gmail.com>
Subject: Re: [ath9k-devel] Pending ath9k bugs
Date: Tue, 2 Jun 2009 10:39:04 +0530	[thread overview]
Message-ID: <20090602050904.GC17632@vasanth-laptop> (raw)
In-Reply-To: <43e72e890906011252s43d2c596m6ec79569f5074837@mail.gmail.com>

 
> BUG_ON in rc.c when using 11n. This could be caused by an incorrect
> assumption in ath9k that the rc priv is correctly for the target rate.
> The issue may be seen when trying to associate and changing between
> legacy and HT rates on SMP systems when mac80211 passes frames on
> different queues due to multiqueue support. If that is indeed the
> reason for the issue we will probably need locking on the rc priv or
> simply to revamp it. I'll send a patch for now to downgrade the BUG_ON
> but we do need a proper fix for this, it just needs more careful
> review.

I agree that rc priv needs proper locking, but I dont think this
particular issue is related to some race in rc priv. As I already
mentioned in one of the mails related to this problem, the root
cause can be a failure in channel set, have we confirmed that?.
I tried to reproduce this on my setup but no luck.

> 
> While on the topic I should mention a welcomed change would be to
> actually revamp ath9k RC to fix it to correctly report MCS rates to
> mac80211. 

This needs complete rewrite of ath9k rate control alg.


Vasanth



  reply	other threads:[~2009-06-02  5:09 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-06-01 18:41 [ath9k-devel] Pending ath9k bugs Luis R. Rodriguez
2009-06-01 18:41 ` Luis R. Rodriguez
2009-06-01 18:48 ` [ath9k-devel] " Luis R. Rodriguez
2009-06-01 18:48   ` Luis R. Rodriguez
2009-06-01 19:30 ` Jiri Slaby
2009-06-01 19:30   ` Jiri Slaby
2009-06-01 19:52 ` [ath9k-devel] " Luis R. Rodriguez
2009-06-01 19:52   ` Luis R. Rodriguez
2009-06-02  5:09   ` Vasanthakumar Thiagarajan [this message]
2009-06-02  5:09     ` Vasanthakumar Thiagarajan

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